When you subscribe we will use the information you provide to send you these newsletters. Sometimes they’ll include recommendations for other related newsletters or services we offer. OurPrivacy Noticeexplains more about how we use your data, and your rights. You can unsubscribe at any time.

City council cabinet member and assistant mayor Nick Small made the remark after another Twitter user posted a picture of the left-wing MP giving a speech from on top of a fire engine to thousands of people in London last night.

The tweeter said Liz Kendall, who is also standing for the leadership of Labour, “could never enthuse a crowd like this."

Cllr Small, cabinet member for education, employment and skills, responded by tweeting back: “I’m more interested in finding a leader who can enthuse 12 million voters @ a general election than 1,000 dinosaurs at a rally”.

Cllr Small’s comments were met with a strong response. @Simon_Mag responded with a series of tweets saying: “Cheers Nick, I was at the rally. First time I’ve been called a dinosaur. The problem is that you (and others) are effectively personally attacking potential voters by referring to them in this way. Whether Corbyn gets in, listen to people talk about a true alternative to this government. Something none of the other candidates have offered”.

And @waller73 tweeted back: “Democracy will decide who the dinosaurs are”.

The battle is intensifying for the Labour leadership, which is also being fought by Liverpool-born Andy Burnham, with the result due on September 12.

The Twitter argument started after Cllr Small posted a link to an article he had written called “Labour is being consumed by Corbynista, ultra-left micro-sects” on the Labour Uncut website.

In this he accuses the Corbyn campaign of dishonesty and “entryism” – where an organisation or political party encourages its members to join another party in order to disrupt it. His accusations follow claims that Tories, extreme left wing parties and even Greens are joining Labour to vote for Corbyn as a way of damaging the party.

Cllr Small wrote in his article: ”Former Militant MP Dave Nellist calls this repopulating the left. That’s breaking the Labour party and replacing it with a new party of the Corbynistas, the ultra-left micro sects, Greens and whoever.”

Cllr Small told the ECHO: "There are many people who’ve been energised by the Labour leadership campaign supporting all candidates who’ve never been involved in politics before. This is a good thing.

"If Andy Burnham, Yvette Cooper or Liz Kendall wins, top of their to-do list should be how the party engages with all these new supporters and brings their passion and enthusiasm on board.

"But I am profoundly worried by some of the people the Corbyn campaign is bringing on board. Many are former Miltants and members of other groups outside the Labour Party, who have no place in our party and want to take our city and our country back 30 years.

"As a Labour activist since I was a teenager, I want Labour to be a party that wins elections and brings about change for ordinary working people. I don’t believe that will happen if Jeremy Corbyn becomes Leader.”